In message <012501c1caf3$516b6160$963fca96@pacesetter.com>, Leigh S.
Jones, KR6X <kr6x@kr6x.com> writes
> I have frequently seen Heathkit SB200's, Collins 30L1's, etc., in
>photos of stations in England, Canada, and Australia for instance.
Leigh,
SB200s and equivalents are considered fairly small amplifiers in the UK
today. A pair of 3-500Zs are fairly standard, but more people are
moving over to 3CX800s/4CX800s.
I can think of a few good reasons for having an amplifier that will
produce more than the legal limit. Here in the UK our limit is 400W but
my amplifier (made by Linear Amp UK.... no connection etc etc, but can
be recommended....) is capable of much more than 400W. Why would I want
that you may ask.....
RTTY contesting which has got to be the most severe test of an amp!!
Even a TL922 gets quite warm running an RTTY contest at 400W (the power
supply gets warm). My amp runs really cool at the 400W level on RTTY so
there is much less chance of failure during a 48hr event. The last
thing I want 40 hours into the contest is amplifier failure!!!!!
Hopefully running the amp well within its limits will prevent failure.
If an amp can last through 48hrs of RTTY contesting, it should walk an
SSB or CW contest!
To get 400W out of my amp requires approximately 20W drive which in turn
means that the spurious outputs and other rubbish from the FT1000mp are
greatly reduced. So, with the radio running well within its limits and
the amplifier well within its limits, hopefully the spectral purity of
my signal will be that much cleaner. The recent discussion on OO
reports and out-of-band emissions when operating close to the band edge
should be a wake-up call here.....
Plus, if the UK ever raises its power limit, it's only a matter of
turning the drive up a little bit more to achieve the new level instead
of having to change the amplifier to remain competitive....
Andrew Williamson GI0NWG / AC6WI
Homepage = http://www.gi0nwg.freeserve.co.uk/
One of the ZL9CI gang
http://www.qsl.net/zl9ci/
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